Ouch!
From the damage to the car it looks like you're pretty lucky to survive that with just a bit of concussion! That's definitely a write-off - if the roof is buckled, especially like that, they very rarely bother to fix it. Also, the door sills are equally as bent, as is the A-pillar.
Where were you coming from in the intersection, and where was the person who hit you coming from? If you were turning right, from the Give Way sign, into the intersection to go where that white Magna wagon is, then I'd assume you'd be at fault.